@sixtyfold/mcp

A local, read-only Model Context Protocol server that gives coding agents version-aware access to Sixtyfold package selection, public APIs, framework examples, option checks, performance guidance, and diagnostics.

The server is developer tooling. It is not imported by chart applications and does not increase the browser bundle size of @sixtyfold/line, @sixtyfold/stock, or any framework adapter.

Connect

Configure an MCP host to launch the npm package over stdio:

{
  "mcpServers": {
    "sixtyfold": {
      "command": "npx",
      "args": ["-y", "@sixtyfold/mcp@1"]
    }
  }
}

You can also install it explicitly:

pnpm add --global @sixtyfold/mcp@1
sixtyfold-mcp

The process writes only MCP JSON-RPC messages to standard output. It requires no Sixtyfold account, API key, or hosted service.

Tools

| Tool | Purpose | | -------------------------------- | -------------------------------------------------------------------------------------------------------------------- | | list_packages | List independent packages, versions, and entry points | | inspect_component_api | Search exact TypeScript symbols, members, signatures, and documented failure contracts within a fixed context budget | | recommend_packages | Return the smallest engine, wrapper, theme, and SSR package set | | generate_integration | Produce verified framework code and optionally adapt a described row or column data shape into typed arrays | | validate_chart_options | Preflight top-level line or stock construction options | | recommend_performance_settings | Suggest grounded render-mode, LOD, and transfer defaults | | diagnose_chart | Focus debugging for LOD, lifecycle, buffer, memory, and rendering symptoms |

All tools declare read-only, non-destructive, idempotent behavior. The server does not modify project files or execute arbitrary shell commands.

On connection the server sends instructions describing the intended tool order and the three integration mistakes that cause most broken charts, so a host does not have to be told how to drive it.

Context budget

Agent context is the scarce resource, so responses are bounded by construction:

• inspect_component_api returns the members that match the query, not every member of the parent type. A hit on one property of a 289-member React props interface returns that property, plus memberCount, membersOmitted, and the membersResource URI to read for the rest. Export- and member-level throws fields preserve documented failure contracts from the declarations.
• An export matched only incidentally returns no members at all; an export matched by its own name returns a bounded preview.
• Each matching export defaults to at most 12 members; override that per-result limit with maxMembers. A single search remains capped at 40 members in total across all results.
• Inlined structural signatures are capped at 400 characters and flagged with signatureTruncated. Read sixtyfold://api/{packageName} for the full type.

A regression test asserts the worst-case search stays inside that budget.

Resources and prompts

The server exposes a compact package catalog, typed-array ownership guidance, performance guidance, minimal licensing guardrails at sixtyfold://guides/licensing, and package-specific API resources under sixtyfold://. User-selectable prompts cover adding, tuning, and reviewing a Sixtyfold integration.

The bundled licensing resource identifies the public licence and the point at which commercial terms are required. It deliberately leaves plans, prices, scope, refunds, support, and version coverage to the live pricing and legal pages. Reading it makes no network request.

The bundled API inventory is generated from the same declaration files shipped by the component packages. CI fails when it drifts from those public entry points.

Integration notes also describe adapter readiness and prop-error recovery, React Activity visibility, Vue once-only stats collection, and Angular stats subscriptions. Timestamp diagnostics distinguish strictly increasing stock streaming from normalized static history; stock append validation happens before buffer transfer.

Privacy and network behavior

@sixtyfold/mcp is local-first:

• stdio transport only in version 1;
• no telemetry or analytics;
• no remote documentation fetch;
• no account, activation, or runtime phone-home;
• no customer chart data leaves the machine through this server.

The selected MCP host and model may have their own data-handling behavior. Review that host separately before supplying proprietary code or data.

Licensing

This package is source-available under the PolyForm Noncommercial License 1.0.0.

For current licensing, commercial terms, and prices, see Licensing and Commercial Terms and Pricing.